941 resultados para Low intensity level lasertherapy (LILT)
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Electron-multiplying charge coupled devices promise to revolutionize ultrasensitive optical imaging. The authors present a simple methodology allowing reliable measurement of camera characteristics and statistics of single-electron events, compare the measurements to a simple theoretical model, and report camera performance in a truly photon-counting regime that eliminates the excess noise related to fluctuations of the multiplication gain.
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Comparative studies of autonomic and somatic reflexes, such as cardiac defense and motor startle, are rare. However, examination of the pattern of covariation, independence, or interference among physiological reflexes may help to clarify their functional significance and elucidate their complex modulation by psychological factors. Here we report the results of a study that examined the pattern of interference of eye-blink startle on subsequent cardiac defense. Participants were 63 students (31 women) distributed into three groups according to the sensory modality of the eliciting stimulus during the startle trials: acoustic high intensity (105 dB), acoustic low intensity (65 dB), and visual modality. Startle trials consisted of 12 presentations of the eliciting stimulus with a duration of 50 ms, instantaneous risetime, and a variable inter-stimulus interval of 16 – 20 s.Defense trials began 20 s after the last startle trial and consisted, for all groups, of 3 presentations of the high intensity acoustic stimulus with a duration of 500 ms and an inter-stimulus interval of 215 s. Results showed a clear interference of the startle trials on the subsequent defense trials when both types of trials shared identical sensory modality (acoustic) independently of intensity: the expected pattern of cardiac defense in the first trial only appeared in the visual modality. Similar interference effects were observed in the skin conductance response. Subjective reactivity to the defense stimulus did not detect differences between conditions.
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O presente estudo avaliou a velocidade da movimentação ortodôntica e as alterações dentárias e esqueléticas na distalização de molares superiores sob influência do laser de baixa intensidade por meio de telerradiografias laterais. A amostra foi constituída por 18 pacientes, portadores de maloclusão Classe II, com idade média inicial de 14,4 anos e divididos em dois grupos: Grupo I - laser e Grupo II - controle. Os pacientes foram tratados com um dispositivo ortodôntico denominado Pêndulo de Hilgers modificado, concomitantemente foi realizado a aplicação do laser de baixa intensidade na região radicular dos primeiros e segundos molares superiores, dos lados direito e esquerdo, nos pacientes do grupo I, sob o seguinte protocolo: 780nm de comprimento de onda, 40mW de potência, 10J/cm² de densidade de energia, 0,4J de energia por ponto durante 10 segundos cada e resultando em energia total de 20,8J. Foram distribuídos 52 pontos por vestibular e palatina dos primeiros e segundos molares superiores. A aplicação do laser foi realizada no dia da ativação da mola de TMA e repetida a cada mês até a sobrecorreção da relação molar. As telerradiografias laterais foram realizadas no início do tratamento (T1), ao final do terceiro mês (T2) e ao final da distalização (T3) com a relação molar sobrecorrigida em aproximadamente 1mm. Após análise cefalométrica foram realizadas comparações das alterações obtidas entre as fases Inicial (T1) e Final (T3) e Inicial (T1) e terceiro mês (T2) e comparadas entre os grupos. Os resultados mostraram inclinação para distal dos primeiros e segundos molares superiores, inclinação vestibular dos incisivos centrais superiores acentuada pela presença dos segundos molares e ausência de alterações dentárias verticais significativas, rotação do plano mandibular no sentido horário e o consequente aumento da altura facial anterior inferior. Concluiu-se que os efeitos do Pêndulo de Hilgers modificado sob a metodologia realizada provocaram alterações predominantemente dentoalveolares e que a movimentação dos primeiros e segundos molares superiores sob efeito da laserterapia, não apresentou diferença estatisticamente significante na velocidade de movimentação ortodôntica e em nenhuma das variáveis estudadas.
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O presente estudo buscou investigar o impacto da resiliência e da autoeficácia sobre o burnout em profissionais de enfermagem. O constructo resiliência no contexto do trabalho refere-se a capacidade de adaptação de forma positiva frente às adversidades que ocorrem no ambiente laboral. A autoeficácia no trabalho representa a percepção do indivíduo sobre as suas próprias competências na execução de tarefas. Já o burnout é compreendido como uma síndrome específica do meio laboral como consequência da cronificação do estresse ocupacional, apresentando três dimensões: a exaustão, o cinismo (despersonalização) e a baixa realização profissional. A amostra da pesquisa foi composta por 82 trabalhadores da área de enfermagem que trabalham em Unidades de Pronto Atendimento UPA s localizadas no estado do Acre. A maior parte dos participantes é do sexo feminino (78%), com idade média de 31 anos (DP=6,8). Para a mensuração das variáveis foram utilizadas a Escala de Resiliência no Trabalho, a Escala de Autoeficácia no Trabalho e a Escala de Caracterização do Burnout, e para coletar os dados sociodemográficos foi aplicado um questionário de autorresposta construído para este estudo. Os dados foram submetidos a análises exploratórias e descritivas, análise de variância (ANOVA), análise de correlação de Pearson e regressão linear múltipla padrão. Os resultados indicaram que os profissionais de enfermagem apresentaram níveis médios de resiliência, autoeficácia e dos componentes exaustão e baixa realização profissional do burnout; e, por sua vez, baixo nível de despersonalização. Constatou-se também correlação entre autoeficácia com dois dos três fatores do burnout: exaustão emocional e decepção no trabalho. Os achados ainda revelaram que resiliência e autoeficácia conjuntamente predizem significativamente ambos os fatores de burnout, exaustão e decepção. No entanto, a variável responsável por esta explicação foi autoeficácia no trabalho, pois apenas ela foi estatisticamente significante para explicar os dois componentes do burnout relatados. Conclui-se que os profissionais que apresentam maior autoeficácia são os que menos sucumbem ao burnout, essa síndrome tão devastadora que ataca de maneira impiedosa os profissionais que lidam no atendimento às pessoas.
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We investigate the learning by exporting hypothesis by examining the effect of exporting on the subsequent innovation performance of a sample of high-technology SMEs based in the UK. We find evidence of learning by exporting, but the pattern of this effect is complex. Exporting helps high-tech SMEs innovate subsequently, but does not make them more innovation intensive. There is evidence that consistent exposure to export markets helps firms overcome the innovation hurdle, but that there is a positive scale effect of exposure to export markets which allows innovative firms to sell more of their new-to-market products on entering export markets. Service sector firms are able to reap the benefits of exposure to export markets at an earlier (entry) stage of the internationalization process than are manufacturing firms. Innovation-intensive firms exhibit a different pattern of entry to and exit from export markets from low-intensity innovators, and this is reflected in different effects of exporting. © 2012 Elsevier Ltd.
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Theory points to the existence of a learning by exporting effect, in which exposure to export markets enhances performance through exposure to the knowledge stocks of trading partners. We investigate the learning by exporting hypothesis by examining the effect of exporting on the subsequent innovation performance of UK high-tech SMEs. We find evidence of learning by exporting, but the pattern of this effect is relatively complex. Exporting helps high-tech SMEs innovate subsequently, but does not make them more innovation intensive. There is also evidence that it is consistent exposure to export markets that helps firms overcome the innovation hurdle, but that there is a positive scale effect of exposure to export markets which allows innovative firms to sell more of their new-to-market products on entering export markets. Service sector firms are able to reap the benefits of exposure to export markets at an earlier (entry) stage of the internationalization process than are manufacturing firms. Firms producing a rapidly changing portfolio of innovative products exhibit higher churn in terms of entry to and exit from export markets than low-intensity innovators, and this is reflected in the effects of entry and exit into and out of such markets.
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Recent years have seen a significant increase in the importance of environmental protection and sustainability to consumers, policy makers, and society in general. Reflecting this, most organizations are at least aware of this new agenda and wish to be seen as taking steps to improve behaviors in this regard. However, there appears to be a gap between this evolving agenda and the comparatively low level of knowledge that marketing managers actually have of the environmental impact of their own functional decisions. We suggest that this low knowledge level may be due, in part, to the marketplace focus of foundational marketing educational programs, and we attempt to show how broadening the horizons of marketing courses can help students (i.e., future managers) more deeply understand the environmental consequences of their actions. We demonstrate the use of a novel business game, based on the Life Cycle Assessment method, as the foundational cornerstone for the development of a broad understanding of the environmental impact of marketing decisions and actions for the entire life cycle of a product—from raw material extraction to ultimate disposal. The results of an empirical study show that this approach increases students’ appreciation for, and understanding of, these fundamental environmental sustainability concepts.
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Prior research on brand extension has provided little evidence on enhancing the evaluation of extremely incongruent extension. Adopting the theoretical framework of schema congruity theory, the author posits that evaluations can be improved if brand personality impressions of both parent brand and extension are complementary. The author coins this as the brand personality complementarity (BPC) principle. Prior to examining BPC effect, cultural-specific brand personality scale was developed to identify universal and indigenous brand personality dimensions. The reason is BPC requires a reliable and valid brand personality scale in order to detect its effect. Following successful identification of the cultural-specific brand personality scale, a total of three experimental studies were done to investigate BPC effect. Specifically, one experimental study identified complementary levels amongst brand personality dimensions, whereas two experimental studies investigated the moderating effect of BPC. Findings from the scale development study reveal that Malaysian brand personality (MBP) scale is a second higher-order factor reflected by first higher-order factors of sophistication, youth, competence, and sincerity. Most importantly, findings from the experimental studies revealed; 1) different BPC levels amongst all possible pairs of MBP dimensions, 2) significant interaction effect of brand extension congruity x BPC, and 3) significant mediation effect of complementarity resolution. Specific findings indicated that when iv text-based stimuli were used to form brand personality impression, even low BPC level improves the evaluations of extremely incongruent extension. However, when visualbased stimuli were used, low BPC level worsen the extension evaluation compared those of the control condition (i.e. without brand personality impression). Implications for both academician and practitioner are discussed.
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High-volume capacitance is required to buffer the power difference between the input and output ports in single-phase grid-connected photovoltaic inverters, which become an obstacle to high system efficiency and long device lifetime. Furthermore, total harmonic distortion becomes serious when the system runs into low power level. In this study, a comprehensive analysis is introduced for two-stage topology with the consideration of active power, DC-link (DCL) voltage, ripple and capacitance. This study proposed a comprehensive DCL voltage control strategy to minimise the DCL capacitance while maintaining a normal system operation. Furthermore, the proposed control strategy is flexible to be integrated with the pulse-skipping control that significantly improves the power quality at light power conditions. Since the proposed control strategy needs to vary DCL voltage, an active protection scheme is also introduced to prevent any voltage violation across the DCL. The proposed control strategy is evaluated by both simulation and experiments, whose results confirm the system effectiveness.
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There is growing popularity in the use of composite indices and rankings for cross-organizational benchmarking. However, little attention has been paid to alternative methods and procedures for the computation of these indices and how the use of such methods may impact the resulting indices and rankings. This dissertation developed an approach for assessing composite indices and rankings based on the integration of a number of methods for aggregation, data transformation and attribute weighting involved in their computation. The integrated model developed is based on the simulation of composite indices using methods and procedures proposed in the area of multi-criteria decision making (MCDM) and knowledge discovery in databases (KDD). The approach developed in this dissertation was automated through an IT artifact that was designed, developed and evaluated based on the framework and guidelines of the design science paradigm of information systems research. This artifact dynamically generates multiple versions of indices and rankings by considering different methodological scenarios according to user specified parameters. The computerized implementation was done in Visual Basic for Excel 2007. Using different performance measures, the artifact produces a number of excel outputs for the comparison and assessment of the indices and rankings. In order to evaluate the efficacy of the artifact and its underlying approach, a full empirical analysis was conducted using the World Bank's Doing Business database for the year 2010, which includes ten sub-indices (each corresponding to different areas of the business environment and regulation) for 183 countries. The output results, which were obtained using 115 methodological scenarios for the assessment of this index and its ten sub-indices, indicated that the variability of the component indicators considered in each case influenced the sensitivity of the rankings to the methodological choices. Overall, the results of our multi-method assessment were consistent with the World Bank rankings except in cases where the indices involved cost indicators measured in per capita income which yielded more sensitive results. Low income level countries exhibited more sensitivity in their rankings and less agreement between the benchmark rankings and our multi-method based rankings than higher income country groups.
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A commonly held view is that creation of excessive domestic credit may lead to inflation problems, however, many economists uphold the possibility that, generous domestic credit under appropriate conditions will result in increases of output. This hypothesis is examined for Japan and Colombia for the period 1950-1993.^ Domestic credit theories are reviewed since the times of Thornton and Smith, until the recent times of Lewis, McKinnon, Stiglitz and of Japanese economists like K. Emi, Tachi R. and others. It is found that in Japan of the Post-War period, efficient financial markets and the decisive role of the government in orienting investment decisions seem to have influenced positively the effectiveness of domestic credit as an output-stimulating variable. On the contrary, in Colombia the absence of the above features seems to explain why domestic credit is not very effective as an output-stimulating variable.^ Multiple regression analyses show that domestic credit is a strong explanatory variable for output increases in Japan and a weak one for Colombia's case in the studied period. For Japan the correlation depicts a positive relationship between the two variables with a decreasing rate very similar to a typical production function. Moreover, the positive decreasing rate is confirmed if net domestic credit is used in the correlations. For Colombia a positive relationship is also found when accumulated domestic credit is used, but, if net domestic credit is the source of correlations, the positive decreasing rate is not obtained.^ Granger causality tests determined causality from domestic credit to output for Japan and no-causality for Colombia at the 1% significance level; the differences are explained by: (1) The low development level of the financial system in Colombia. (2) The nonexistence of consistent domestic credit policy to foster economic development. (3) The lack of an authoritative orientation in the allocation of financial resources and the nonexistence of long range industrialization programs in Colombia that could channel productively credit resources. For the system of equations relating domestic credit and exports, the Granger causality tests determined no-causality between domestic credit and exports for both Japan and Colombia also at the 1% significance level. ^
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Knowledge of cell electronics has led to their integration to medicine either by physically interfacing electronic devices with biological systems or by using electronics for both detection and characterization of biological materials. In this dissertation, an electrical impedance sensor (EIS) was used to measure the electrode surface impedance changes from cell samples of human and environmental toxicity of nanoscale materials in 2D and 3D cell culture models. The impedimetric response of human lung fibroblasts and rainbow trout gill epithelial cells when exposed to various nanomaterials was tested to determine their kinetic effects towards the cells and to demonstrate the biosensor's ability to monitor nanotoxicity in real-time. Further, the EIS allowed rapid, real-time and multi-sample analysis creating a versatile, noninvasive tool that is able to provide quantitative information with respect to alteration in cellular function. We then extended the application of the unique capabilities of the EIS to do real-time analysis of cancer cell response to externally applied alternating electric fields at different intermediate frequencies and low-intensity. Decreases in the growth profiles of the ovarian and breast cancer cells were observed with the application of 200 and 100 kHz, respectively, indicating specific inhibitory effects on dividing cells in culture in contrast to the non-cancerous HUVECs and mammary epithelial cells. We then sought to enhance the effects of the electric field by altering the cancer cell's electronegative membrane properties with HER2 antibody functionalized nanoparticles. An Annexin V/EthD-III assay and zeta potential were performed to determine the cell death mechanism indicating apoptosis and a decrease in zeta potential with the incorporation of the nanoparticles. With more negatively charged HER2-AuNPs attached to the cancer cell membrane, the decrease in membrane potential would thus leave the cells more vulnerable to the detrimental effects of the applied electric field due to the decrease in surface charge. Therefore, by altering the cell membrane potential, one could possibly control the fate of the cell. This whole cell-based biosensor will enhance our understanding of the responsiveness of cancer cells to electric field therapy and demonstrate potential therapeutic opportunities for electric field therapy in the treatment of cancer.
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The current study examines the effects of an online workshop pertaining to classroom behavior management on teacher self-efficacy, attitudes, motivation, knowledge, and practices. In addition, information about teacher utilization of the Internet, their opinions about professional development, and experiences with classroom management were collected. Participants included 57 1st through 5th grade special and regular education teachers. Eligible teachers were those who teach an academic subject and had at least one child in the classroom they considered as disruptive. Teachers were randomized to either a training or waitlist group. Classroom observations of teacher practices and questionnaires were utilized. Teachers in the training group participated in two assessment points, baseline and post-workshop, and received access to the online course immediately following the baseline assessment. Teachers in the waitlist group participated in three assessment points, baseline, post-workshop, and follow-up, and received access to the online course immediately following the post-workshop assessment. Findings show that all teachers had access to the Internet at home and at school and used it on a daily basis. The majority of teachers indicated having some past training on all the techniques that were presented in the online workshop. All teachers expressed satisfaction with the workshop, indicating that it should be offered again. Post-workshop, findings showed significant group differences in knowledge with a large effect for the training group scoring higher than the waitlist group on a quiz. Secondly, group differences in self-efficacy, knowledge, and attitudes with teachers’ past-training as a moderator, was examined. Past-training was not found to be a significant moderator of self-efficacy, knowledge, or attitudes. However, the main effect for training group was significant for attitudes. In addition, teacher attitudes, but not knowledge and self-efficacy, significantly predicted motivation to implement. Next, the moderating effect of barriers on motivation and classroom management skill implementation was examined. Barriers were not found to be a significant moderator. Lastly, the training group was observed to be significantly more effective at giving commands compared to the waitlist group. The current study demonstrates the potential of a low-intensity online workshop on classroom management to enhance the accessibility of teacher professional development.
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High-resolution pollen and dinoflagellate cyst records from sediment core M72/5-25-GC1 were used to reconstruct vegetation dynamics in northern Anatolia and surface conditions of the Black Sea between 64 and 20 ka BP. During this period, the dominance of Artemisia in the pollen record indicates a steppe landscape and arid climate conditions. However, the concomitant presence of temperate arboreal pollen suggests the existence of glacial refugia in northern Anatolia. Long-term glacial vegetation dynamics reveal two major arid phases ~64-55 and 40-32 ka BP, and two major humid phases ~54-45 and 28-20 ka BP, correlating with higher and lower summer insolation, respectively. Dansgaard-Oeschger (D-O) cycles are clearly indicated by the 25-GC1 pollen record. Greenland interstadials are characterized by a marked increase in temperate tree pollen, indicating a spread of forests due to warm/wet conditions in northern Anatolia, whereas Greenland stadials reveal cold and arid conditions as indicated by spread of xerophytic biomes. There is evidence for a phase lag of ~500 to 1500 yr between initial warming and forest expansion, possibly due to successive changes in atmospheric circulation in the North Atlantic sector. The dominance of Pyxidinopsis psilata and Spiniferites cruciformis in the dinocyst record indicates brackish Black Sea conditions during the entire glacial period. The decrease of marine indicators (marine dinocysts, acritarchs) at ~54 ka BP and increase of freshwater algae (Pediastrum, Botryococcus) from 32 to 25 ka BP reveals freshening of the Black Sea surface water. This freshening is possibly related to humid phases in the region, to connection between Caspian Sea and Black Sea, to seasonal freshening by floating ice, and/or to closer position of river mouths due to low sea level. In the southern Black Sea, Greenland interstadials are clearly indicated by high dinocyst concentrations and calcium carbonate content, as a result of an increase in primary productivity. Heinrich events show a similar impact on the environment in the northern Anatolia/Black Sea region as Greenland stadials.
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The Acquired Immune Deficiency Syndrome (AIDS), considered today one chronic nature of the disease due to the advent of antiretroviral therapy (TARV), brings to individuals living with this disease, difficulties related to social interaction and adaptation to new physical condition and the routines imposed by the treatment. This reality has a strong impact on the lives of these people in order of overcoming them use coping strategies, Coping. In this context, the aim of this study was to characterize the epidemiological, clinical and life habits of people living with AIDS and analyze the coping strategies used with the situation of the disease, according to sociodemographic, clinical and life habits. This is a cross-sectional study with a quantitative approach. The sample consisted of 331 people registered at the clinic of the Hospital Giselda Trigueiro (HGT), located in Natal / RN, who had scheduling for outpatient medical consultation from January to August 2014. The study was approved by the Ethics Committee the Federal University of Rio Grande do Norte with the Presentation of Certificate for Ethics Assessment (CAAE), paragraph 16578613.0.0000.5537. The data of social characterization showed predominance of men (52%), young people (42%) coming from the capital (58%), mulatto (53%), single (56%), heterosexual (79%), poor (68 %). With regard to clinical aspects it has been found that most held the first HIV testing for less than five years (60%) had signs and symptoms of AIDS before the examination (90%) were hospitalized (90%) started ART for less than five years (60%) believe they have good knowledge of the disease (75%) and believe that their health has improved (92%). For lifestyle, it became clear that most do not consume alcohol (71%), do not smoke (88%) and do not use illicit drugs (92%) and never used condoms before diagnosis (62%) and only 192 (58%) use the currently codon. With regard to the reference was higher coping focused modes of emotion, although the problem solving has been the second most common. The mean scores of women, workers, religious and never abandoned the treatment were higher for all factors. Having a partner, living with family members and support in the treatment had higher average scores for various factors, coinciding in the confrontation, withdrawal and social support. As for the leisure and physical exercise also dominated the modes focused on emotion as was seen in the correlation between the time of treatment, education and family income and IEEFL factors, although with low intensity. The profile of the study population confers with national characteristics, suggesting feminization, internalization, pauperization, heterosexual, increased CD4 cell count and viral load reduction during treatment and maintaining healthy lifestyle habits. Coping strategies used were more focused on emotion. In this context, it is understood that the identification of these strategies can facilitate care planning, encouraging such persons to adapt to stressors with the situation of the disease